feat: 添加 Dashboard 供应商成本统计功能

- 新增 stats_daily_provider 表存储每日供应商统计数据
- 实现供应商维度的数据聚合服务
- Dashboard API 返回 provider_summary 供应商汇总数据
- 前端新增 DoughnutChart 环形图组件
- Dashboard 新增供应商成本分布可视化卡片
- 移除重复的请求次数/费用趋势折线图

Closes #110

Co-authored-by: RWDai <27391645+RWDai@users.noreply.github.com>

src/services/system/cleanup_scheduler.py

@@ -208,7 +208,7 @@ class CleanupScheduler:
                         return
 
                     # 非首次运行，检查最近是否有缺失的日期需要回填
-                    from src.models.database import StatsDailyModel
+                    from src.models.database import StatsDailyModel, StatsDailyProvider
 
                     yesterday_business_date = today_local.date() - timedelta(days=1)
                     max_backfill_days: int = SystemConfigService.get_config(
@@ -223,6 +223,7 @@ class CleanupScheduler:
                     # 获取 StatsDaily 和 StatsDailyModel 中已有数据的日期集合
                     existing_daily_dates = set()
                     existing_model_dates = set()
+                    existing_provider_dates = set()
 
                     daily_stats = (
                         db.query(StatsDaily.date)
@@ -245,6 +246,17 @@ class CleanupScheduler:
                             stat_date = stat_date.replace(tzinfo=timezone.utc)
                         existing_model_dates.add(stat_date.astimezone(app_tz).date())
 
+                    provider_stats = (
+                        db.query(StatsDailyProvider.date)
+                        .filter(StatsDailyProvider.date >= check_start_date.isoformat())
+                        .distinct()
+                        .all()
+                    )
+                    for (stat_date,) in provider_stats:
+                        if stat_date.tzinfo is None:
+                            stat_date = stat_date.replace(tzinfo=timezone.utc)
+                        existing_provider_dates.add(stat_date.astimezone(app_tz).date())
+
                     # 找出需要回填的日期
                     all_dates = set()
                     current = check_start_date
@@ -256,15 +268,18 @@ class CleanupScheduler:
                     missing_daily_dates = all_dates - existing_daily_dates
                     # 需要回填 StatsDailyModel 的日期
                     missing_model_dates = all_dates - existing_model_dates
+                    # 需要回填 StatsDailyProvider 的日期
+                    missing_provider_dates = all_dates - existing_provider_dates
                     # 合并所有需要处理的日期
-                    dates_to_process = missing_daily_dates | missing_model_dates
+                    dates_to_process = missing_daily_dates | missing_model_dates | missing_provider_dates
 
                     if dates_to_process:
                         sorted_dates = sorted(dates_to_process)
                         logger.info(
                             f"检测到 {len(dates_to_process)} 天的统计数据需要回填 "
                             f"(StatsDaily 缺失 {len(missing_daily_dates)} 天, "
-                            f"StatsDailyModel 缺失 {len(missing_model_dates)} 天)"
+                            f"StatsDailyModel 缺失 {len(missing_model_dates)} 天, "
+                            f"StatsDailyProvider 缺失 {len(missing_provider_dates)} 天)"
                         )
 
                         users = (
@@ -288,6 +303,10 @@ class CleanupScheduler:
                                     StatsAggregatorService.aggregate_daily_model_stats(
                                         db, current_date_local
                                     )
+                                if current_date in missing_provider_dates:
+                                    StatsAggregatorService.aggregate_daily_provider_stats(
+                                        db, current_date_local
+                                    )
                                 # 用户统计在任一缺失时都回填
                                 for (user_id,) in users:
                                     try:
@@ -329,6 +348,7 @@ class CleanupScheduler:
 
                 StatsAggregatorService.aggregate_daily_stats(db, yesterday_local)
                 StatsAggregatorService.aggregate_daily_model_stats(db, yesterday_local)
+                StatsAggregatorService.aggregate_daily_provider_stats(db, yesterday_local)
 
                 users = db.query(DBUser.id).filter(DBUser.is_active.is_(True)).all()
                 for (user_id,) in users:

src/services/system/stats_aggregator.py

@@ -17,6 +17,7 @@ from src.models.database import (
     RequestCandidate,
     StatsDaily,
     StatsDailyModel,
+    StatsDailyProvider,
     StatsSummary,
     StatsUserDaily,
     Usage,
@@ -286,6 +287,68 @@ class StatsAggregatorService:
         )
         return results
 
+    @staticmethod
+    def aggregate_daily_provider_stats(db: Session, date: datetime) -> list[StatsDailyProvider]:
+        """聚合指定日期的供应商维度统计数据
+
+        Args:
+            db: 数据库会话
+            date: 要聚合的业务日期
+
+        Returns:
+            StatsDailyProvider 记录列表
+        """
+        day_start, day_end = _get_business_day_range(date)
+
+        # 按供应商分组统计
+        provider_name_expr = func.coalesce(Usage.provider_name, "Unknown")
+        provider_stats = (
+            db.query(
+                provider_name_expr.label("provider_name"),
+                func.count(Usage.id).label("total_requests"),
+                func.sum(Usage.input_tokens).label("input_tokens"),
+                func.sum(Usage.output_tokens).label("output_tokens"),
+                func.sum(Usage.cache_creation_input_tokens).label("cache_creation_tokens"),
+                func.sum(Usage.cache_read_input_tokens).label("cache_read_tokens"),
+                func.sum(Usage.total_cost_usd).label("total_cost"),
+            )
+            .filter(and_(Usage.created_at >= day_start, Usage.created_at < day_end))
+            .group_by(provider_name_expr)
+            .all()
+        )
+
+        results = []
+        for stat in provider_stats:
+            existing = (
+                db.query(StatsDailyProvider)
+                .filter(and_(StatsDailyProvider.date == day_start, StatsDailyProvider.provider_name == stat.provider_name))
+                .first()
+            )
+
+            if existing:
+                record = existing
+            else:
+                record = StatsDailyProvider(
+                    id=str(uuid.uuid4()), date=day_start, provider_name=stat.provider_name
+                )
+
+            record.total_requests = stat.total_requests or 0
+            record.input_tokens = int(stat.input_tokens or 0)
+            record.output_tokens = int(stat.output_tokens or 0)
+            record.cache_creation_tokens = int(stat.cache_creation_tokens or 0)
+            record.cache_read_tokens = int(stat.cache_read_tokens or 0)
+            record.total_cost = float(stat.total_cost or 0)
+
+            if not existing:
+                db.add(record)
+            results.append(record)
+
+        db.commit()
+        logger.info(
+            f"[StatsAggregator] 聚合日期 {date.date()} 供应商统计完成: {len(results)} 个供应商"
+        )
+        return results
+
     @staticmethod
     def get_daily_model_stats(db: Session, start_date: datetime, end_date: datetime) -> list[dict]:
         """获取日期范围内的模型统计数据（优先使用预聚合）
@@ -613,6 +676,7 @@ class StatsAggregatorService:
         while current_date < today_local:
             StatsAggregatorService.aggregate_daily_stats(db, current_date)
             StatsAggregatorService.aggregate_daily_model_stats(db, current_date)
+            StatsAggregatorService.aggregate_daily_provider_stats(db, current_date)
             count += 1
             current_date += timedelta(days=1)